1. Field of the Invention
This invention pertains to safety attachments for vehicles and more particularly to a method using an attachment to block the beams of headlights of oncoming vehicles to prevent dangerous and even blinding glare, mainly in the eyes of older drivers, particularly on two lane roads, and especially when it is raining.
2. Background of the Invention
Driving requires effective coordination of visual, motor and cognitive skills. Visual skills are pushed to their limit at night by decreased illumination and by disabling glare from oncoming headlights. Glare is proportional to headlight brightness so increasing headlight brightness also increases potential glare for oncoming drivers, particularly on two lane roads and especially in the rain. This problem is worse for older drivers because of their increased intraocular light scattering, glare sensitivity and photstress recover time.
Modern vehicle headlights are electrically operated, positioned in pairs, one or two on each side of the front of a vehicle. A headlight system produces a low and a high beam. High beams are used when other vehicles are not present on the oncoming side of the road. Low beams have stricter control of upward light, and direct most of their light downward and either rightward (in right-traffic countries) or leftward (in left-traffic countries) to provide safe forward visibility without excessive glare.
A night driving problem, particularly for older drivers on two lane roads, and especially when it is raining, is that oncoming high beams can be blinding, and even oncoming low beams can cause dangerous glare. That is because, with increasing age, cataracts in the eye's lens scatter the oncoming light.
A cataract is the clouding of the normally transparent lens within the eye. The lens is located directly behind the pupil and normally assists in focusing light for clear vision. As the cataract worsens it prevents light from coming through the pupil and focusing clearly on the retina. Early changes may be very minor, but as the process continues symptoms of blurred vision, light sensitivity, glare and night driving difficulties increase. The nighttime driving difficulties are mainly caused by headlight glare. It takes a typical driver ten seconds to recover from headlight glare and this time increases with age. At 30 miles an hour a car travels an eighth of a mile in 10 seconds.
This nighttime driving problem has intensified with vision-disabling nighttime glare from three types of headlights mounted on the front of motor vehicles: “high intensity discharge” (HID) lights that appear blue, auxiliary lights such as “fog lamps”, and headlights mounted high on various light trucks (sport utility vehicles, pickups and vans).
Finally, nighttime driving difficulties from headlights and glare are exacerbated in the rain and especially heavy rain to the point that an older driver can be blinded.